A new naphthoquinone analogue and antiviral constituents from the root of Rhinacanthus nasutus

Abstract

Rhinacanthus nasutus (L.) Kurz (Acanthaceae) is known as traditional medicine for the treatment of fungal and herpes virus infections. A new naphthoquinone racemate, rhinacasutone (1) together with seven known compounds, rhinacanthone (2), rhinacanthins C, D, N, Q, and E (3–7), and heliobuphthalmin (8) were isolated from root of R. nasutus. Their structures were determined on the basis of extensive spectroscopic methods, including 1D-, 2D-NMR and MS data. All the isolated compounds were tested for their antiviral activities against PR8, HRV1B, and CVB3-infected vero cells. Compounds 3–6 exhibited significant antiviral activities with the IC₅₀ value ranging from 0.03 to 23.7 μM in all three infections.

Keywords:

• Rhinacasutone
• rhinacanthin
• Rhinacanthus nasutus
• antivirus